Featured Research

from universities, journals, and other organizations

Searching For The 'Real' Waterworld

Date:
July 10, 2003
Source:
European Space Agency
Summary:
At the recent ESA co-sponsored 'Towards Other Earths' conference, nearly 250 of the world's leading experts in planet detection discussed the strategy for finding Earth-like worlds. Alain Léger and colleagues of the Institut d'Astrophysique Spatiale, France, described a new class of planets that could be awaiting discovery: 'waterworlds'.

At the recent ESA co-sponsored 'Towards Other Earths' conference, nearly 250 of the world's leading experts in planet detection discussed the strategy for finding Earth-like worlds. Alain Léger and colleagues of the Institut d'Astrophysique Spatiale, France, described a new class of planets that could be awaiting discovery: 'waterworlds'.

According to Léger and his colleagues, these waterworlds would contain about six times the mass of Earth, in a sphere twice as wide as our planet. They would possess atmospheres and orbit their parent star at roughly the same distance that the Earth is from the Sun. Most excitingly, an ocean of water entirely covers each world and extends over 25 times deeper than the average depth of the oceans on Earth.

A hundred kilometres deep

According to calculations, the internal structure of a waterworld would consist of a metallic core with a radius of about 4000 kilometres. Then there would be a rocky mantle region extending to a height of 3500 kilometres above the core's surface, covered by a second mantle made of ice up to 5000 kilometres thick. Finally, an ocean blankets the entire world to a depth of 100 kilometres, with an atmosphere on top of this.

With twice the radius of the Earth, they will be easily spotted by the Eddington spacecraft, which is designed to detect planets down to half the size of the Earth. "A waterworld passing in front of a star, somewhat cooler than the Sun, will cause a dimming in the stellar light by almost one part in a thousand. That's almost ten times larger than the smallest variation Eddington is designed to detect. So, waterworlds – if they exist – will be a very easy catch for Eddington," says Fabio Favata, ESA's Eddington Project Scientist.

The CNES/ESA mission Corot, which is a smaller, precursor mission to Eddington due for launch around 2005, may also be just able to glimpse them, if they are close enough to their parent stars.

Origins of life

Scientists are now asking if such worlds could support life, and what would it be like, especially since water is a prime ingredient for life on Earth. While waterworlds seem to have everything to sustain life, there is a big question mark over whether they could actually allow it to start in the first place.

One of the leading theories for life's origin in deep oceans is that it requires hot springs on the ocean floor, heated by volcanic activity like the 'black smokers' found here on Earth. On a waterworld however, 5000 kilometres of ice separate the ocean floor from any possible smokers. On the other hand, a water-surface origin may still be possible.

Perhaps the only way to know if anything lives on a waterworld will be to study them with ESA's habitable-planet-finding mission, Darwin. When it launches in around 2014, this flotilla of spacecraft will look for tell-tale signs of life in the atmospheres of any planets, including waterworlds.


Story Source:

The above story is based on materials provided by European Space Agency. Note: Materials may be edited for content and length.


Cite This Page:

European Space Agency. "Searching For The 'Real' Waterworld." ScienceDaily. ScienceDaily, 10 July 2003. <www.sciencedaily.com/releases/2003/07/030710091215.htm>.
European Space Agency. (2003, July 10). Searching For The 'Real' Waterworld. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2003/07/030710091215.htm
European Space Agency. "Searching For The 'Real' Waterworld." ScienceDaily. www.sciencedaily.com/releases/2003/07/030710091215.htm (accessed October 20, 2014).

Share This



More Space & Time News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Comet Siding Spring Grazes Mars' Atmosphere

Comet Siding Spring Grazes Mars' Atmosphere

Newsy (Oct. 19, 2014) — A comet from the farthest reaches of the solar system passed extremely close to Mars this weekend, giving astronomers a rare opportunity to study it. Video provided by Newsy
Powered by NewsLook.com
Latin America Launches Communications Satellite

Latin America Launches Communications Satellite

AFP (Oct. 17, 2014) — Argentina launches a home-built satellite, a first for Latin America. It will ride a French-made Ariane 5 rocket into orbit, and will provide cell phone, digital TV, Internet and data services to the lower half of South America. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
This Week @ NASA, October 17, 2014

This Week @ NASA, October 17, 2014

NASA (Oct. 17, 2014) — Power spacewalk, MAVEN’s “First Light”, Hubble finds extremely distant galaxy and more... Video provided by NASA
Powered by NewsLook.com
Saturn's 'Death Star' Moon Might Have A Hidden Ocean

Saturn's 'Death Star' Moon Might Have A Hidden Ocean

Newsy (Oct. 17, 2014) — The smallest of Saturn's main moons, Mimas, wobbles as it orbits. Research reveals it might be due to a global ocean underneath its icy surface. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins